The use of a flexible endoscope (fiberscope) for examining the interior wall of a body passage such as the colon is well known. Flexible fiberoptic colonoscopy plays an important role in the preoperative and postoperative diagnostic evaluation of the condition of the large bowel for cancer, it being recognized that carcinoma of the colon stands as the second most common cause of cancer deaths. Although instrumentation necessary for examination of the entire colon is available, the use of such equipment presently requires the services of a highly skilled colonoscopist, in contrast to those of a general endoscopist, if the risks of perforating the colon and life-threatening hemorrhaging are to be kept low. Even experienced examiners are known to fail in trying to reach and examine the entire colon because of anatomical variations and pathological alterations. Persistence in trying to overcome such obstacles can lead to complications even when the procedure is carried out by an experienced colonoscopist.
This invention is concerned with reducing the above limitations in employment of fiberoptic colonoscopy and, in general, with decreasing the hazards and complexities associated with the use of currently-available flexible endoscopes in conducting visual diagnostic internal examination of the colon and other body passages. Another aspect of the invention lies in providing an improved endoscope equipped with means adjacent its distal end to assist in the advancement of the endoscope through a tubular body passage.
In brief, the combination includes a sleeve which extends about and is secured to the distal end portion of a flexible endoscope. The sleeve has an outer tubular wall of resilient flexible material which, in combination with the endoscope or with an inner wall in direct engagement with the endoscope, defines an expandable annular chamber. At least one conduit communicates with the chamber and with a pulsatile fluid source for supplying fluid for repetitious expansion and contraction of the chamber. The outer wall has a multiplicity of resilient hollow protrusions, each of which is movable between a partially-inverted retracted condition (when the chamber is unexpanded) and an outwardly- and rearwardly-projecting extended condition when the chamber is expanded by the pressure fluid. Direct engagement between the resilient protrusions and the wall of the body passage helps to advance the endoscope along that passage.
References illustrative of the prior art are U.S. Pat. Nos. 3,485,237, 2,855,934, 3,895,637, 2,356,659, 3,911,927, 3,168,092, 3,982,544, 3,669,099, 3,794,041 and 3,665,928.
Other advantages, features, and objects of the invention will become apparent from the specification and drawings.